The Greatest Commandment: Love God and Neighbor
Asked to rank the law, Jesus refuses the ranking and gives a direction instead: love God with everything, and love your neighbor as yourself. Everything God commands hangs on those two.
Matthew 22:34–40: The Greatest Commandment
Jesus answers a testing lawyer by naming love for God and love for neighbor as the load-bearing center of the law, not an addition to it. The whole law and the prophets hang on these two.
Mark 12:28–34: The Greatest Commandment
Jesus answers the question about the greatest commandment by joining wholehearted love of God with love of neighbor, and he tells the agreeing scribe that he is close to the Kingdom but not yet inside it.